I posted this over in general firearms discussion, but didn't get a response.

Okay, I understand that these little kits require welding, but that doesn't deter me too much. How easy is it to make the breech face? Obviously this is considered an 80% receiver build, but what part is the receiver? I only ask because I've seen ads in SGN for the receiver sideplates, so I'm wondering if I have to make those myself or if it's okay to assemble the kit on them.